Set-screw.



CHARLES G. LuNnHoLM,

PATENT oEEioE.

oF LAs VEGAS', NEVADA.

SET-SCREW.

4Specification of Letters Batent.

Applicatonled December 28, 1908. Serial No. 469,545.

To .all whom 'it may concern:

Be lit known that I, CHARLES G. LUND- HoLM, a citizen of the United States, residing` at Las Vegas, in the county of Lincoln and State of Nevada, have invented new and useful' Improvements in Set-Screws, of which the following is a specication.

The object of my invention is to provide a set-screw which will be locked in the. screw-threaded socket when Yscrewed tightly therein and prevent the accidental removal therefrom of the set-screw, except a wrenchbe applied thereto for that purpose. I accomplish this object by means of the device described herein and shown in the accompanying drawings, in whichs- Figure 1- is a side view of a set-screw partly broken away embodying my inven- `tion. Fig. 2fis a side view partly broken away of a set-screw expander; F ig. 3 is a side View of a set-screw in place in the screwthreaded socket with the set-screw expander in position therein.

An ordinary set-screw 4 is provided with a longitudinal slit 5 extending from the screw threaded end of a portion of the length of the set-screw, providing means whereby the bifurcations of the threaded ends of the screw may be spread apart and thereby securely lock the set-screw in the screw-threaded socket when it is tightly screwed therein; In order to properly 4ex? pand the bifurcations of the set-screw when it is screwed home, I have caused to be made in the screw-threaded end of the set-screw, a conical recess 6 for the reception of the conical end 7 of the screw-expander 8. This conical expander is first placed into the screw-threaded socket and the set-screw is screwed thereinto and against the expander. As' the expander is crowded down ti htly against the shaft 9, the furcations o the tightly grasp the female threads surrounding the saine and prevent the accidental unternal force applied to the nut l0 by .wrench or otherwise will be necessary to remove the set-screw. There may be more than. one slit the end ofthe screw may be of any configuration, providing the walls thereof have inclined bearing faces which will cause the projecting furcations of the set-screw to expand when any object is crowded between them, and the screw expander may be of any configuration provided it has bearing faces adapted to contact with the inclined walls of the recess and expand the urcations when the expander iscrowded therebetween. Having described my invention what I claimas new and desire to secure by Letters Pgatent is l. The combination of a threaded bolt provided with a vertically slotted and recessed end, and an expander having one end .adapted to seat in the recessed end of the bolt, the opposite end being cupped to forni an annular engaging edge.

2. The combination of a threaded bolt provided' with a vertically slotted and conically recessed end, of an expanding button provided with a conicalend adapted to enter the recessed end of the bolt and prevent an accidental movement of the bolt, the opposite end of the button being cupped to form day of December, 1908.

C. G. LUNDIIOLM. yVlitnesses:

HENRY T. HAZARD,

set-screw will be expanded against and EDMUND A. STRAUSE.

Patented oet. 12, isoa- .in the end of the set-screw and the recess inan annular engaging edge, whereby` to prescrewing of the set-screw therefrom, and ex- 

